Signal processing techniques for estimating characteristic parameters of a signal or for transforming a signal into a more desirable form are well known. Such techniques are advantageously utilized in such diverse fields as acoustics, data communications, radar and speech recognition. For example, in a speech recognition system, a speech signal is processed to extract characteristic information encoded in frequency, amplitude and time. This information is then processed to extract various recognizable features in the speech signal which are used to aid in the recognition process. Since the performance of the overall speech recognition system is largely dependent on the accuracy of the original extraction process, highly efficient signal processing techniques are required. Although prior art signal processing techniques have generally proven effective, there is a need for more efficient and powerful techniques to improve overall system performance.